The term “Acqua Alta” is commonly used in Venice for the exceptional tide peaks that occur periodically in the Venetian Lagoon. This unique and spectacular phenomenon occurs mainly between autumn and spring, when the astronomical tides are reinforced by the prevailing seasonal winds which hamper the usual reflux. The main winds involved are the scirocco, which blows northbound along the Adriatic Sea, and the bora, which has a specific local effect due to the shape and location of the Venetian lagoon.
The phenomenon largely depends on three main factors:
• an astronomical component, which results from the movement and alignment of celestial bodies, principally the Moon; this component is dependent upon the laws of the astronomical mechanics and can be accurately predicted for the long run;
• a geophysical component, primarily dependent upon the geometric shape of the basin, which amplifies or reduces the astronomical component and, because it is dependent upon the laws of the physical mechanics, can be also computed and accurately predicted for the long run;
• a meteorological component, linked to a large set of variables, such as the direction and strength of winds, the location of barometric pressure fields and their gradients, precipitation. This component can only be forecast for the very short run and is probably the principal determinant of acqua alta emergencies.
This “Acqua Alta” spreads particularly in the St. Mark’s basin and in the lower areas of the city next to the Grand Canal. Despite some diseases to the local population, it has become a significant attraction for tourists from all over the world who come to Venice. Anyway, if you decide to come to our Best Western Premier Hotel Sant’Elena, don’t worry, our hotel is in a quiet area, higher than the St. Mark’s basin and not interested by this unique and particular phenomenon.